Advanced Performance Notes

This guide focuses on practical frame-time control for serious sketches and installations.

Performance model

Frame cost mainly comes from:

1. geometry count and draw calls
2. shader complexity and overdraw
3. post-processing pass count
4. texture size and update frequency
5. feedback/accumulation pipelines

High-impact optimizations

1) Prefer instancing for repeated meshes

• use instanced paths for large repeated object sets.
• avoid per-object materials where one shared material can work.

2) Keep render target sizes intentional

• .tex() and FBO defaults can be larger than needed for a specific effect.
• choose width/height based on visual need, not screen maximum by default.

3) Minimize post FX in inner loops

• each FX pass adds full-frame work.
• stack only passes that materially improve the aesthetic target.

4) Control accumulation scope

• autoClear(<1) can become expensive in complex pipelines.
• isolate trail effects to specific outputs/scenes instead of global usage.

5) Reuse geometry and materials

• avoid allocating new geometry/material objects in update.
• update transforms/uniforms rather than recreating scene objects.

6) Use non-global mode in host apps

• reduces accidental cross-instance coupling.
• simplifies profiling and lifecycle ownership in app runtimes.

7) Manage input and event workloads

• input hooks run often; keep handlers lightweight.
• move heavy work to frame update paths with explicit budgets.

Runtime tuning checklist

• set clear FPS targets per deployment profile (desktop, mobile, projector).
• profile with and without FX to identify largest pass deltas.
• verify behavior in Chromium and Firefox if both are target environments.
• validate memory growth during long runs (hours, not seconds).

Debugging hotspots

• sudden frame drops:

- check recent shader/pipeline additions, especially bloom/blur stacks.

• stutter under feedback chains:

- reduce render target resolution or pass count.

• long startup time:

- preload textures and simplify first-frame scene initialization.

Production posture

• ship with conservative defaults and opt-in heavy effects.
• treat visual parity checks as regression tests for performance tradeoffs.
• use browser smoke + scene-specific profiling before release tags.